The Lubavitcher Rebbe said in a speech that the messiah won’t be a Hasid, but rather someone from the non-Hasidic Jewish population.

This would, presumably, preclude the Rebbe himself, R’ Menachem Mendel Schneerson, from being the Messiah.

Schneerson delivered the statement in this 1951 speech. The relevant portion comes at the section marked נג, in the fifth paragraph there. This was sent to me this week.

Schneerson in this speech is speaking of the importance of “accepting the yoke” of service to God, and offers this tangential narrative about the first Lubavitcher Rebbe (the English translation is mine, and a bit loose in relaying the idioms):

The first Lubavitcher Rebbe was brought to three “olamsher” (non-Hasidic) great rabbis, and when with one of them, that rabbi asked the first Lubavitcher Rebbe: “Who will be the messiah — a Hasid or a non-Hasidic Jew?” The first Lubavitcher Rebbe responded: “The messiah will be a non-Hasidic Jew.” The rabbi asked back, “Why?” and the first Lubavitcher Rebbe responded: “Because if the messiah were a Hasid, the non-Hasidic Jews wouldn’t want to follow him out of the diaspora; but if the messiah were a non-Hasidic Jew, he’d also attract the Hasidim.”

These kinds of statements citing previous rebbes are generally seen as endorsing the concept implied. This would suggest that Schneerson agreed with this statement he’s quoting from the first Lubavitcher Rebbe.